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Re: repeat items in a list

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From Michael Selik <michael.selik@gmail.com>
Newsgroups comp.lang.python
Subject Re: repeat items in a list
Date Tue, 29 Mar 2016 22:05:16 +0000
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I prefer itertools.chain.from_iterable to the sum trick.

>>> from itertools import chain
>>> lst = list('abc')
>>> list(chain.from_iterable([s]*3 for s in lst))
['a', 'a', 'a', 'b', 'b', 'b', 'c', 'c', 'c']



On Tue, Mar 29, 2016 at 5:28 PM Vito De Tullio <vito.detullio@gmail.com>
wrote:

> Random832 wrote:
>
> > How do you turn ['a', 'c', 'b'] into ['a', 'a', 'a', 'c', 'c', 'c', 'b',
> > 'b', 'b']?
>
> >>> sum([[e]*3 for e in ['a', 'c', 'b']], [])
> ['a', 'a', 'a', 'c', 'c', 'c', 'b', 'b', 'b']
>
>
> --
> By ZeD
>
> --
> https://mail.python.org/mailman/listinfo/python-list
>

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Thread

repeat items in a list beliavsky@aol.com - 2016-03-26 15:12 -0700
  Re: repeat items in a list Cameron Simpson <cs@zip.com.au> - 2016-03-27 10:05 +1100
  Re: repeat items in a list Erik <python@lucidity.plus.com> - 2016-03-26 23:23 +0000
    Re: repeat items in a list beliavsky@aol.com - 2016-03-26 16:36 -0700
      Re: repeat items in a list Rob Gaddi <rgaddi@highlandtechnology.invalid> - 2016-03-28 17:30 +0000
        Re: repeat items in a list Chris Angelico <rosuav@gmail.com> - 2016-03-29 08:25 +1100
          Re: repeat items in a list Antonio Caminero Garcia <tonycamgar@gmail.com> - 2016-03-29 01:43 -0700
        Re: repeat items in a list Erik <python@lucidity.plus.com> - 2016-03-28 23:14 +0100
  Re: repeat items in a list Mark Lawrence <breamoreboy@yahoo.co.uk> - 2016-03-26 23:28 +0000
    Re: repeat items in a list beliavsky@aol.com - 2016-03-26 16:54 -0700
      Re: repeat items in a list Paul Rubin <no.email@nospam.invalid> - 2016-03-26 22:35 -0700
  Re: repeat items in a list Antonio Caminero Garcia <tonycamgar@gmail.com> - 2016-03-27 01:02 -0700
    Re: repeat items in a list Antonio Caminero Garcia <tonycamgar@gmail.com> - 2016-03-27 01:30 -0700
    Re: repeat items in a list Jussi Piitulainen <jussi.piitulainen@helsinki.fi> - 2016-03-27 14:09 +0300
  Re: repeat items in a list larudwer <larudwer@freenet.de> - 2016-03-27 11:52 +0200
    Re: repeat items in a list Antonio Caminero Garcia <tonycamgar@gmail.com> - 2016-03-27 04:13 -0700
      Re: repeat items in a list larudwer <larudwer@freenet.de> - 2016-03-28 13:36 +0200
        Re: repeat items in a list Random832 <random832@fastmail.com> - 2016-03-28 10:04 -0400
        Re: repeat items in a list Vito De Tullio <vito.detullio@gmail.com> - 2016-03-29 23:25 +0200
        Re: repeat items in a list Michael Selik <michael.selik@gmail.com> - 2016-03-29 22:05 +0000
        Re: repeat items in a list Peter Otten <__peter__@web.de> - 2016-03-30 17:52 +0200

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